For now, every other day. When I train to run I do two runs at a pace slightly above comfortable. One day I run at a comfortable pace that I can carry and go longer then the other two runs, basically a long run. One day is strictly speed work. Though I haven't run a track in a while. I do my best speed work on a track. I warm up for two laps at a slow pace. If my average pace is 9 minutes a mile during my two runs described above that will break down to 2:15 a lap. My speed will be 2:00 or 2:05 minutes around the track for my speed work. I run one lap at this pace and then walk half the track to recover. Then I repeat. When I first starting doing this a while ago I was dead after about 4 laps. Then do a cool down of two laps around the track at a slow pace. Not only did I do speed work I did 2.5 miles on my total count for the day. 1 mile for the warm up/ cool down, one mile of speed work, half a mile during the recovery between sets. However, since you just started I would recommend what I said in the post above and for your to run for time now and then one day a week when your on the track pick it up around one of the turns. See where you are in a couple of weeks and then pick it up from there.
I'm not sure if there is anything on reading for your breathing. Maybe consult a few books like "Galloway's Book on Running" by Jeff Galloway. My breathing technique is two in/two out. If that makes sense. Basically I start with a shallow, normal inhale and then with a deep inhale to fill up the lungs then I exhale half and push out the last half. When my dad and I ran when I was a teenager he wouldn't let me run with ear phones on and instead made me concentrate on breathing. So try that.